Investment Securities (Unrealized Losses on Available for Sale and Held to Maturity Securities) (Details) $ in Thousands	Jun. 30, 2018 USD ($) security	Dec. 31, 2017 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	171	105
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 125,754	$ 75,375
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(2,302)	(581)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	26,360	27,761
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(1,082)	(759)
Securities in a continuous unrealized loss position, fair value	152,114	103,136
Securities in a continuous unrealized loss position, unrealized losses	$ (3,384)	$ (1,340)
U. S. Treasury securities and obligations of U.S. Government sponsored entities (“GSE”) and agencies [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	5	2
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 3,920	$ 1,967
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(64)	(30)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	2,928	3,150
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(93)	(84)
Securities in a continuous unrealized loss position, fair value	6,848	5,117
Securities in a continuous unrealized loss position, unrealized losses	$ (157)	$ (114)
Residential collateralized mortgage obligations - GSE [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	29	11
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 37,358	$ 19,237
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(686)	(205)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	7,891	8,788
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(450)	(299)
Securities in a continuous unrealized loss position, fair value	45,249	28,025
Securities in a continuous unrealized loss position, unrealized losses	$ (1,136)	$ (504)
Residential mortgage backed securities - GSE [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	50	35
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 37,000	$ 21,770
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(715)	(141)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	4,046	3,074
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(172)	(58)
Securities in a continuous unrealized loss position, fair value	41,046	24,844
Securities in a continuous unrealized loss position, unrealized losses	$ (887)	$ (199)
Obligations of state and political subdivisions [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	69	42
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 22,187	$ 11,594
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(472)	(82)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	2,532	2,717
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(45)	(35)
Securities in a continuous unrealized loss position, fair value	24,719	14,311
Securities in a continuous unrealized loss position, unrealized losses	$ (517)	$ (117)
Trust preferred debt securities – single issuer [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	2	4
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 0	$ 0
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	0	0
Securities in a continuous unrealized loss position, 12 months or longer, fair value	1,402	2,349
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(87)	(132)
Securities in a continuous unrealized loss position, fair value	1,402	2,349
Securities in a continuous unrealized loss position, unrealized losses	$ (87)	$ (132)
Corporate debt securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	7	7
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 14,273	$ 11,967
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(268)	(98)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	7,546	7,662
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(234)	(150)
Securities in a continuous unrealized loss position, fair value	21,819	19,629
Securities in a continuous unrealized loss position, unrealized losses	$ (502)	$ (248)
Other debt securities [Member]
Debt and Equity Securities, FV-NI [Line Items]
Securities in a continuous unrealized loss position, number | security	9	4
Securities in a continuous unrealized loss position, less than 12 months, fair value	$ 11,016	$ 8,840
Securities in a continuous unrealized loss position, less than 12 months, unrealized losses	(97)	(25)
Securities in a continuous unrealized loss position, 12 months or longer, fair value	15	21
Securities in a continuous unrealized loss position, 12 months or longer, unrealized losses	(1)	(1)
Securities in a continuous unrealized loss position, fair value	11,031	8,861
Securities in a continuous unrealized loss position, unrealized losses	$ (98)	$ (26)